AstraZeneca acknowledged on Tuesday morning that a press release about its U.S. coronavirus vaccine trial was based on data through Feb. 17, and promised to release more complete results that are "consistent with" the interim data within the next 48 hours.

Why it matters: The National Institute of Allergy and Infectious Diseases (NIAID) released an unusual statement early Tuesday expressing concerns that AstraZeneca's release may have used "outdated information" that "may have provided an incomplete view of the efficacy data."

• NIAID urged the company to work with the independent Data and Safety Monitoring Board (DSMB), which was cited in the release, to "review the efficacy data and ensure the most accurate, up-to-date efficacy data be made public as quickly as possible."
• AstraZeneca committed in its statement to "immediately engage" with the DSMB to share its primary analysis, which it said is "consistent with the interim analysis."

Driving the news: Anthony Fauci, who serves as director of NIAID, called AstraZeneca's possible use of outdated information an "unforced error," stressing on Tuesday that "this is very likely a very good vaccine."

• The British-Swedish pharmaceutical company said an interim analysis of its Phase III U.S. trial had found the vaccine to be 79% effective at preventing symptomatic COVID-19 and 100% effective against severe disease and hospitalization.
• AstraZeneca also said the data showed no serious side effects among the more than 20,000 participants who received at least one dose — news that was seen as likely to bolster global confidence in a vaccine that was briefly suspended in European countries over concerns about possible blood clots.

What they're saying: "If you look at it, the data are quite good, but when they put it into the press release it wasn't completely accurate," Fauci said on ABC's "Good Morning America."

• "So we have to keep essentially trying as hard as we can to get people to understand that there are safeguards in place. And I think the Data and Safety Monitoring Board picking up this discrepancy was an example of the safeguard," he continued.
• "And at the end of the day, Robin, all of this is going to be decided by the FDA. They will independently go over every bit of data themselves and not rely on any interpretation from anyone including the company."

Go deeper: Science is suffering from low research standards